In the 1970s, Cambodia suffered one of the largest genocides of the twentieth century under the government of the Khmer Rouge (KR). To provide justice to survivors, Cambodia has convened a special tribunal ("the KR trials") to try the KR leadership in public hearings. If the trials promote feelings of justice among Cambodian survivors and reduce the desire for revenge, they may be able to reduce the burden of trauma-related mental health problems, such as posttraumatic stress disorder (PTSD). However, if the KR trials revive traumatic memories, they may increase the severity or prevalence of PTSD. The proposed research has three specific aims: 1) to identify the average change in knowledge of the trials, attitudes (revenge and justice) and mental health outcomes from 3 months prior to the KR trials to one year after their conclusion;2) to characterize the longitudinal trajectory of Cambodian attitudes and trauma-related mental health, such as PTSD, among individuals;3) to identify characteristics that predict individual trajectories in attitudes (of revenge and justice) and mental health outcomes. The guiding hypothesis is that the KR trials will reduce the prevalence of PTSD by reducing the desire for revenge and increasing feelings of satisfaction with justice pertaining to violations of the KR era. A longitudinal study will be conducted over a three year period of time to test that hypothesis. With funding from the United States Institute of Peace, our group conducted a baseline study of attitudes (of revenge and justice) and trauma-related mental health, in a national probability sample (N = 1,017) from all 24 provinces in Cambodia, prior to the start of the KR trials. Three additional waves of data collection, using a face-to-face interview will be conducted with the same persons, at 2 months, 14 months, and 26 months after the start of the project. The four waves of data collection (one conducted prior to the start of this project) will span from prior to the KR trials to one year after their completion. The high prevalence of trauma sequelae in post-conflict settings suggests that individually-oriented treatments may not be adequate to meet public mental health needs. Findings from the proposed research will help to determine whether societal interventions to promote justice can reduce the prevalence and severity of trauma-related distress. PUBLIC HEALTH RELEVANCE: The purpose of this project is to determine whether a human rights tribunal, the Khmer Rouge trials in Cambodia, can promote feelings of justice and reduce mental illness, such as post-traumatic stress disorder, in civilians exposed to severe trauma. Since individually-oriented treatments, such as medications, may be inadequate to meet public mental health needs in societies exposed to war or terrorism, tribunals may be useful and cost-effective mental health interventions.